Method of covering a structure having defining walls and an open top

ABSTRACT

A method of covering a structure having walls defining an interior, the walls having an upper peripheral edge defining an open top. A first step involves positioning a base unit within the interior of the structure, the base unit defining a drainage opening. A second step involves extending supporting cables from the base unit to the upper peripheral edge of the walls. A third step involves supporting a funnel shaped tarp on the supporting cables. The funnel shaped tarp has an upper cone and a lower chute. A top peripheral edge of the upper cone is secured to the upper peripheral edge of the walls. The lower chute extends down to the drainage opening in the base unit. The open top of the structure is covered by the funnel shaped tarp and precipitation is directed by the upper cone and the lower chute to the drainage opening.

FIELD

The present invention relates to a method of covering a structure having defining walls and an open top, such as a floating roof tank, with tarps.

BACKGROUND

The present method arose out of a contract to blast with abrasives and then coat an interior of a floating roof tank. The tank was emptied and the floating roof was set down on legs, leaving the top side of the floating roof and the remainder of the interior of the tank open to the environment. A false roof supported by scaffolding was considered, but false roof was expensive and the scaffolding was going to be in the way of the work to be performed. Tarps were tried, but they could not support the weight of ice, snow and rain over the required span, and were susceptible to becoming sails in high winds.

SUMMARY

According there is provided a method of covering a structure having walls defining an interior, the walls having an upper peripheral edge defining an open top. A first step involves positioning a base unit within the interior of the structure, the base unit defining a drainage opening. A second step involves extending supporting cables from the base unit to the upper peripheral edge of the walls. A third step involves supporting a funnel shaped tarp on the supporting cables. The funnel shaped tarp has an upper cone and a lower chute. A top peripheral edge of the upper cone is secured to the upper peripheral edge of the walls. The lower chute extends down to the drainage opening in the base unit. The open top of the structure is covered by the funnel shaped tarp and precipitation is directed by the upper cone and the lower chute to the drainage opening.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features of the invention will become more apparent from the following description in which reference is made to the appended drawings, the drawings are for the purpose of illustration only and are not intended to in any way limit the scope of the invention to the particular embodiment or embodiments shown, wherein:

FIG. 1 is a side elevation view of a base unit within the interior of a tank structure with supporting cables extending from the base unit to the upper peripheral edge of the walls, in accordance with the teachings of the method.

FIG. 2 is a side elevation view of the base unit illustrated in FIG. 1, after placement of the funnel tarp.

FIG. 3 is a top plan view of the tank structure illustrated in FIG. 1.

DETAILED DESCRIPTION

A method of covering a structure having defining walls and an open top will now be described with reference to FIG. 1 through 3.

The method involves the steps of:

As shown in FIG. 1, a base unit 10 is positioned within a structure 12. Base unit 10 has tie rings 14, a ring bar 16, a drive motor 18, wheels 20, and a rotatable spool 22. Rotatable spool 22 contains a tarp 24, tarp 24 being initially wrapped around rotatable spool 22. In the embodiment shown, base unit 10 is a cart 25. Structure 12 has walls 26 and a floor 28. Floor 28 may be a floating roof. Walls 26 have an exterior 27. Walls 26 define an interior 30 of structure 12. In this embodiment, structure 12 is a large tank 32. Walls 26 have an upper peripheral edge 34 which define an open top 36. Base unit 10 defines a drain opening 38. Base unit 10 may be placed within tank 32 using a crane (not shown) to lower base unit 10 onto floor 28. Base unit 10 can then be wheeled into the center of floor 28 using wheels 20. Upon positioning base unit 10 in the center of floor 28, base unit is secured to floor 28 using one or more tie-downs 40. Tie-downs 40 may consist of rope, chain, or other securing material. Tie-downs 40 secure base unit 10 to floor 28 by connecting to tie rings 14. In the embodiment shown, base unit 10 has 4 tie rings 14 to secure tie downs 40 to, although any number of tie rings 14 may be used. Supporting cables 42 are extended from base unit 10 to upper peripheral edge 34 of tank 32. This may be accomplished by securing supporting cables 42 to upper peripheral edge 34 and lowering supporting cables 42 down to interior 30. Supporting cables 42 can then be secured to ring bar 16. Referring to FIG. 3, tarp 24 consists of an upper cone 44, and a lower chute 46. Upper cone 44 has a top peripheral edge 48. Attached to top peripheral edge 48 are flaps 50. Tarp 24 is funnel shaped.

Once supporting cables 42 are in place, top peripheral edge 48 of tarp 24 is secured to upper peripheral edge 34 as shown in FIG. 2. In order to secure tarp 24 to upper peripheral edge 34, tarp 24 must be unwound from rotatable spool 22. Tarp 24 may be drawn upwards by first securing top peripheral edge 48 to winches (not shown) that run along supporting cables 42. Tarp 24 is drawn upwards, supported by supporting cables 42 until top peripheral edge 48 of tarp 24 reaches upper peripheral edge 34 of structure 12, unwinding tarp 24 from rotatable spool 22 at the same time. When top peripheral edge 48 is drawn up to reach upper peripheral edge 34, top peripheral edge 48 is secured to upper peripheral edge 34. Flaps 50 overlap upper peripheral edge 34, and are secured to exterior 27 of walls 26. Lower chute 46 is connected to drain opening 38. Drain opening 38 connects to a drain 52. Drain 52 may be positioned above or below floor 28.

Once tarp 24 is unwound and secured to upper peripheral edge 34, tarp 24 covers open top 36, and acts as a funnel for any precipitation that contacts tarp 24. Supporting cables 42 help support of tarp 24. Precipitation is funneled down upper cone 44, into lower chute 46, and directed into drain opening 38. Flaps 50 are used to seal tank 32, by preventing any precipitation from slipping between walls 26 and top peripheral edge 48. This way, all the precipitation that would otherwise have contacted floor 28 is directed down into drain opening 38. Drain opening 38 directs precipitation into drain 52, where it is removed from tank 32. In this manner, work may be done to interior 30. Such work may include shot blasting, applying protective coating to prevent corrosion or any other manner of construction of restorative work.

Referring to FIG. 2, chemical injectors 54 are positioned along top peripheral edge 48 of funnel shaped tarp 24. Chemical injectors 54 are used to dispense de-icing chemicals onto upper cone 44. Chemical injectors 54 can dispense anti-freezing fluids that will remove any ice, snow or hail that may collect on tarp 24. This ensures that there is no build up of excess ice, snow or hail on tarp 24, as such a build up could potentially damage tarp 24. The use of chemical injectors 54 allows this system to be used in any environmental conditions, at any time of year. Alternatively, pressure washers (not shown) may be used to clear away any build-up of ice, snow or hail on tarp 24.

Tarp 24 is disassembled by detaching top peripheral edge 48 from upper peripheral edge 34 and winding tarp 24 around rotatable spool 22. Drive motor 18 turns rotatable spool 22 to wind tarp 24. Ring bar 16 prevents tarp 24 from snagging while tarp 24 is being re-wound. Once tarp 24 is wound around rotatable spool 22, supporting cables 42 are removed, and tie downs 40 are detached from tie rings 14. Base unit 10 may then be removed using a crane (not shown) to lift base unit 10 out of tank 32.

In this patent document, the word “comprising” is used in its non-limiting sense to mean that items following the word are included, but items not specifically mentioned are not excluded. A reference to an element by the indefinite article “a” does not exclude the possibility that more than one of the element is present, unless the context clearly requires that there be one and only one of the elements.

It will be apparent to one skilled in the art that modifications may be made to the illustrated embodiment without departing from the spirit and scope of the invention as hereinafter defined in the Claims. 

1. A method of covering a structure having walls defining an interior, the walls having an upper peripheral edge defining an open top, comprising the steps of: positioning a base unit within the interior of the structure, the base unit defining a drainage opening; extending supporting cables from the base unit to the upper peripheral edge of the walls; supporting a funnel shaped tarp on the supporting cables, the funnel shaped tarp having an upper cone and a lower chute, a top peripheral edge of the upper cone being secured to the upper peripheral edge of the walls, the lower chute extending down to the drainage opening in the support, such that the open top of the structure is covered by the funnel shaped tarp and precipitation is directed by the upper cone and the lower chute to the drainage opening.
 2. The method of claim 1, including a step of positioning one or more chemical injectors along the top peripheral edge of the funnel shaped tarp to dispense de-icing chemicals into the upper cone, as required.
 3. The method of claim 1, including a step of using a cart as the base unit.
 4. The method of claim 1, including a step of incorporating a rotating spool into the base unit and extending and retracting the funnel shaped tarp by rotating the spool.
 5. The method of claim 1, including a step of incorporating a cable attachment bar into the base unit and attaching the supporting cables to the cable attachment bar.
 6. The method of claim 5, the cable attachment bar being in the form of a ring.
 7. The method of claim 1, including the step of incorporating tie downs into the base unit and anchoring the base unit. 